/Engine/Source/Developer/HierarchicalLODUtilities/Public/IHierarchicalLODUtilities.h
Computes which LOD level of a Mesh corresponds to the given Distance (calculates closest ScreenSize with distance)
int32 ComputeStaticMeshLODLevel ( const [TArray](API\Runtime\Core\Containers\TArray)< [FStaticMeshSourceModel](API\Runtime\Engine\Engine\FStaticMeshSourceModel) > & SourceModels, const [FStaticMeshRenderData](API\Runtime\Engine\FStaticMeshRenderData) * RenderData, const float ScreenSize )